Process for even and level dyeing of filament nylon fabrics



Unite atent r 2,952,506 Patented Sept. 13, 1960 fiice PROCESS FOR EVENAND LEVEL DYEING OF FEAR/TENT NYLON FABRICS No Drawing. Filed Aug. 24,1956, Ser. No. 605,941 Claims. (Cl. 8-55) This invention relates to theeven dyeing of textile fabrics, and more particularly to the even andlevel dyeing of fabrics composed of filaments of a polycarbonamide, morefamiliarly known as nylon.

In the past the commercial practice of dyeing the synthetic linearpolycarbonamides more familiarly known as nylon has been carried out bymeans of the dispersed or acetate dyestuifs. These dispersed dyestuffshave great covering power for nylon yarns and are not highly sensitiveto the normal variations found in such yarns. However, the dispersed oracetate colors lack fastness to light and to Washing. In contrast, theanionic dyestufis best exemplified by the classes of acid and directdyes have extremely good fastness to both light and washing on nylon. Ithas not been commercially feasible to utilize the anionic dyestutfs inthe majority of nylon filament dyeings, however, since those dyestufisare extremely sensitive to variations between difierent fibers anddifferent parts of the same fibers. Nylon yarns which have been spun atdifierent times or from ditferent lots of polymer demonstrate thesevariations most clearly. Frequently yarns spun at different times aredyed to diiferent shades with the anionic dyestuflfs when dyed bystandard dyeing procedures. As a result the nylon fabrics dyed withanionic dyes are often colored in an uneven fashion, showing streaks andshade depth variations in knitted goods, and barr elfects, warp streaksand the like in woven goods. The inability to secure even dyeing ofnylon yarns and fabrics is believed to be due to slight variations inthe chemical compositions of the parent polymers, to variations inorientation due to slight differences in the drawing to which the yarnsare subjected either in spinning and processing of the yarn, or in themechanical action of the textile machinery used in the knitting orweaving of the fabrics, and perhaps to other causes as well. Thisinability to evenly dye nylon yarns and fabrics with the anionicdyestulfs has curtailed the large scale use of such dyestuffs for dyeingthe nylon materials on which they exhibit excellent light and washfastness properties.

The primary object of the present invention is to provide a new andimproved process for dyeing polycarbonamide textile articles. A furtherobject is to provide a process for dyeing nylon yarns evenly and levellyby means of anionic dyestufis Without the resulting streaks and shadedepth variation that have previously characterized the use of theanionic dyestuffs for the dyeing of nylon fabrics. Other objects willappear from the description hereinafter.

In general the objects of this invention are accomplished by the processof dyeing polycarbonamide textile articles which comprises dyeing thearticles in an aqueous dyeba-th containing an anionic dyestufi selectedfrom the group consisting of direct dyes, acid dyes, acid metallizeddyes, and mordant acid dyes and a substituted imidazoline compoundselected from the group consisting of (l) a salt of an imidazolinehaving the general. formula wherein R is selected from the groupconsisting of alkyl, phenyl, hydroxyalkyl, and carboxyalkyl radicals andR is an open aliphatic chain consisting of from ten to 18 carbon atoms,such as I-butyl-2-hexadecyl-irnidazoline, 1- benzyl-Z-hexadecylimidazoline, 1-(2-hydroxyethy1)-2- heptadecyl-imidazoline,I-(Z-hydroxyethyl) 2 heptadecenyl-imidazoline, andl-(2-hydroxyethyl)-2-undecylimidazoline, (2) a quaternary imidazoliniumcompound having the general formula wherein R and R are selected fromthe group consisting of alkyl, phenyl, hydroxyalkyl and carboxyalkylradicals, R is an open aliphatic chain consisting of from ten to 18carbon atoms and X is a halogen, suchas,l,ldi-(Z-hydroxyethyl)-2-heptadecyl imidazolinium chloride,1,1-di-(2-hydroxyethyl) 2 heptadecenyl-imiclazolinium chloride,Z-tridecyl-l-hydroxyethyl-l-benzyl-imidazolinium chloride and1,1-dibutyl-2-hexadecyl-imidazolinium chloride, and (3) a quaternaryimidazolinium compound having the general formula EEC-N t wherein R andR are selected from the group consisting of hydroxyalkyl, alkalimetal-substituted hydroxyalkyl, and alkali metal-substitutedcarboxyalkyl radicals and R is an open aliphatic chain consisting offrom ten to 18 carbon atoms, such as l,l-di(2-hydroxyethyl)-2-heptadecylimidazolinium hydroxide and the disodium salt ofZ-nndecyl-l-(2-hydroxyethyl)-1-(carboxymethyl) imidazolinium hydroxide.It has now been found that quite even and level dyeings of nylon yarnsand fabrics can be achieved by means of the anionic dyestuifs claimedabove if the dyeing is carried out in an acidic dyebath containing asubstituted imidazoline compound of one of the abovedescribed types.

The amount of the substituted imidazoline compounds which can be used inthe process of the present invention can vary between one and ten timesthe weight of the dyestuffs employed. Many of the anionic dyestuffssuitable for use in the process may be used to dye nylon fabrics evenlyand levelly when employing as little as one to two times the weight ofthe dyestufi of the substituted imidazoline compounds. However, withothers of the anionic dyestuffs, although these amounts of thesubstituted imidazoline compounds give even dyeings from fiber to fiberthey may result in unlevel dyeings, i.e. unequal penetration as betweenthe fibers. With these dyestuffs both even and level dyeings of nylonfabrics may be acheived by increasing the ratio of the substitutedimidazoline compounds to the dyestufit employed to a value of from about6 to 10 times the weight of the dyestuff. Normally a ratio ofapproximately 41 to 6 times the weight of the dyestufl for the amount ofthe substituted imidazoline compounds is preferred.

The synthetic linear polycarbonamides, more familiarly known as nylons,to which the process of this invention is applicable are of the generaltype described in U.S. Patents 2,071,250; 2,071,253 and 2,130,948. Thecontemplated polycarbonamides comprise the reaction products of linearpolymer-forming compositions containing amideforming groups, for examplereaction materials consisting of bifunctional molecules containing tworeactive groups which are complementary to reactive groups in othermolecules and which include the. complementary amideforming groups.These polycarbonamides are of two distinct types. Those synthetic linearpolycarbonamides which comprise the self-polymerization products ofmonoamino monocarboxycyclic acids containing at least five carbon atomsin the chain separating the amino and carboxyl' groups and thosesynthetic linear polycarbonamides derived from the reaction of suitablediamines with suitable dicarboxylic acids in substantially equimolaramounts. It is. to be understood that reference herein tothe aminoacids, diamines, and dicarboxylic acids is intended to include theequivalent amide-forming derivatives of those reactants. Upon hydrolysisthe amino acid polycarbonamides yield the amino acid hydrochloride, andthe diamine-dicarboxyclic acid polycarbonamides yield the dicarboxyclicacid and the diamine hydrochloride. Further, the average number ofcarbon atoms separating the amide groupsin the polycarbonamides is atleast two.

These polycarbonamides contain recurring amide r ps:

I II

wherein R is a member of the group of hydrogen and monovalenthydrocarbon radicals, as a part of main chain of atoms of the polymer.Particularly useful polycarbonamides in the present invention are thesimple unsubstituted polycarbonamides, such as those formed by thereaction of tetramethylene diamine with adipic acid, tetramethylenediamine with suberic acid, tetrarnethylene diamine with sebacic acid,hexamethylene diamine with adipic acid, hexamethylene diamine withsuberic acid, hexamethylene diamine with sebacic acid, or thepolymerization product of epsilon-caprolactam. In addition, polymersformed from the reaction of two ormore di-. amines with dicarboxylicacids and/or two or more di carboxylic acids with diamines arecontemplated in the practice of the-instant invention.

Most types of anionic dyestufis function with the process. of thisinvention. The two most common classes of anionic dyestuffs and twowhich give excellent light and wash fastness when used on nylons are theacid and direct dyes, but other classes of anionic dyestuffs may beemployed in this process as well, such as acid metallized and mordantacid or chrome dyes. Thus, at least four of the recognized classes ofanionic dyes, the direct dyes, the acid dyes, the acid metallized dyesand the mordant acid or chrome dyes can be successfully applied tonylons by the process of this invention. Examples of certain of thedirect dyestuffs which have been successfully employed to dye nylonfabricslevelly and uniformly by the process of this invention includePaper Yellow 3GXA (CI 364), Chrysophenine (CI 365), Chlorantine FastYellow SGLL (CI 346), Calcodur Orange GL (CL 653), Calcodur Red SBL (CL278), Triazol Fast Scarlet B (CI 382). Congo Red (CI 370), Diarnine FastRed FA- CF (CI 419), and Diphenyl Violet EV Supra (CI 394). Examples ofacid dyestufis which may be employed include Pontacyl Dark Green (CI247), Amacid Red 3B (CI 280), Benzyl Red G (CI 275), Brilliant CroceineScarlet MOO (CI, 252), Anthraquinone Violet 3RAv (CI 1080) and AlizarinFast Light Blue C (CI 108-8). Examples of mordant acid or chromedyestuifs which may be used include Omega Chrome Orange G (CI 274),Eriochrome Blue Black R (CI 202), Calcochrome Black T (CI 203), ChromeYellow A (CI 219), and Calcochrome Alizarine Gray 2BLS (Pr. 206).Examples of acid metallized dyestufls which may be employed includeNeolan Blue 2G (Pr. 144), Neolan Navy Blue RLG (Pr. 561), and ChromacylBlack W (Pr. 143). Not all dyestuffs of each class of anionic dyesenumerated will dye nylon yarns or fabrics equally as well, as is wellknown. However, the best dyes from among each class can easily beselected, and a large number of the dyestuffs in each named class can beeffectively utilized to dye nylon materials evenly and levelly. by theprocess of this invention,

The conditions of dyeing employed in theprocess of the present inventionare substantially those of the normal dyeing procedure with theparticular classes of. anionic dyes employed. That is, with all of thenamed classes of anionic dyestuffs dyeing is usually carried out at atemperature of from about 200 to about 210 F. and at a pH of from about2 to about 5.5. The preferred pH with the acid and direct dyestufi's isfrom about 3 to about 5.

The amount of dyestulf employed and the volumeof dye-.

bath are the same as those commonly used in the acid and direct dyeingof woolen, cellulosic and other type fibers. The length of time of thedyeing to result in even and, level dyeings of nylon is generally fromabout 1 to about 4 hours.

The mechanics of carrying out the dyeing are not. critical and may bevaried to suit the normal dyeing practice. That is, the fabric may beentered into the bath cold and the bathslowly raised to dyeingtemperature after all the ingredients have been added, or the fabric maybe added to the bath first and the dyestufi and substituted imidazolinecompound added afterwards. The order of addition of components to thedyebath, is a matter of choice.

Although the process of the present invention does not require the useof other dispersing agents inaddition to the dyestulf and thesubstituted imidazoline compounds.

referred to above, it is sometimes of advantage in obtaining greaterlevelling as well as eveness of dyeing to employ in the dyebath inaddition to the named ingredients a non-ionic dispersing agent. Suchnon-ionic dispersing agents as those containing the condensationproducts. of polyglycols with higher fatty acids, higher fatty alcohols,amides of higher fatty acids, or long chain alkyl substituted phenolscan be added to the dyebath of the present invention to assist inobtaining more level dyeings on certain nylon constructions. Thenon-ionic dispersingagents may be used in concentrations of from about0.1% to about, 4%. The use of the non-ionic dispersing agents not onlyimproves the levelness of penetration of the dyes from fiber to fiberbut also insures that those fibers on the interior of the skein areevenly dyed with those on the exterior. Consequently, when dyeingcertain closely woven fabrics such as taffetas it is preferred toinclude a non-ionic dispersing agent of the above-described type. in thedyebath.

It has also been found that the substituted imidazoline,

compounds are effective to convert an unevenly dyed nylon fabric to anevenly dyed one by subjecting the,

dyed fabric to an aqueous treatment therewith. Thus, an

unevenly dyed talfeta or chiffon fabric displaying streaks.

and shadevariations throughout the piececan be rendered even and levelby treating for several hours in a bath containing one of thesubstituted. imidazoline. compounds for example, 1,1 di (2-hydroxyethyl)-2-heptadecenyl imidazolinium chloride, in the same general amounts thatare used to evenly dye such fabrics by the process of this invention.The bath may be maintained at an acidic pH at or near the boil until thedyeing has become even and level. If such procedure is not suflicient toproduce an even and level dyeing of verybadly streaked fabrics, it isalso possible to treat the fabric in an alkaline bathcontaining one ofthe substituted imidazolme compounds and after the dyestuff originallyprescut on the fabric has been substantially removed into solution, thenadjusting the pH of the bath to an acidic pH and thereby effecting aredyeing of the fabric with the same dyestuif, but in a completely evenand level manner. Although it is not required that such treating bathscontain a non-ionic dispersing agent, the presence of such an agent, forexample the condensation product of one mole of stearyl alcohol with 20moles of ethylene oxide is preferred, since less of the substitutedirnidazoline compound is required when a non-ionic dispersant is alsopresent. By this means previously uneven dyeings can be converted toeven dyeings on nylon fabrics and knitted goods.

The applications of the principles of this invention are moreparticularly illustrated in the examples below. Parts are by Weightunless otherwise stated.

EXAMPLE I A dyebath was prepared containing 0.25% Pontacyl Dark Green G(CI 247), 1.4% of 1,1-di-(2-hydroxyethyl)-2-heptadecenyl-imidazoliniumchloride, and 5% glacial acetic acid in 40 volumes of water, allpercentages being based on Weight of the fabric to be dyed. A speciallyknit nylon tricot was employed in the dyeing. This nylon tricot fabricwas made up of seven different samples of nylon yarn, spun and drawnunder different conditions so as to display different dyeing rates. Thefabric was knit on a 14 gauge machine with 20 ends of each yarn sampleknit side by side in the following order: (1) a sample of normalcommercial 70 denier, 34 filament nylon yarn, (2) a sample of the sameyarn count spun on a pilot plant spinning machine in the normal manner,(3) a sample of the same yarn drawn at a 3.2% higher than normal drawratio, (4-) a sample of the same yarn drawn at a 2.6% lower than normaldraw ratio, (5) a sample of the yarn spun from the same batch employinga higher than normal air flow in the spinning machine, (6) a sample ofyarn spun from the same batch employing C. lower than normal temperatureof the melt entering the spinneret, and (7) a sample of the samecommercial 70 denier normally spun nylon yarn as in 1) above. Thespecially knit tricot fabric employed was knit from yarns havingsufficient differences in the spinning and drawing thereof todemonstrate pronounced dilferences in shade upon dyeing with an acid ordirect dyestuff. One part of the specially knit tricot fabric wasentered into the bath and the temperature of the bath slowly raised to200 F. The bath was held at this temperature for 3 hours. The shadedepth variations between the seven different yarns making up the tricotfabric were hardly noticeable to the eye. The gray scale ratings of thedifferences at each knitting junction of the specially knit tricotfabric are based upon the International Geometric Grey Scale of theSociety of Dyers and Colorists, wherein a rating of 5 representsnegligible shade variation from the next proceding sample or sectionthereof, a rating of 4 represents noticeable variation, a rating of 3represents appreciable variation, 2. rating of 2 represents considerablevariation, a rating of 1 represents much variation and a plus or minusindicates slightly more or less than the given rating. The grey scaleratings of the fabric dyed in the above manner are set out in Table Ibelow.

One part 'of the same specially knit nylon tricot fabric employed abovewas dyed in a dyebath containing 0.25%

Pontacyl Dark Green G (CI 247 and 5% of ammonium slowly to 200 acetatein 40 volumes of water, the percentages being based on the weight of thefabric dyed, in the same manner as above. The shade depth variationsbetween the seven different yarns composing the specially knit tricotfabric were quite noticeable as between the yarns. The grey scaleratings of the difference at each knitting junc- A dyebath was preparedcontaining the following ingredients: 0.25% Pontacyl Dark Green G (CI247), 0.5% of l,l-(2-hydroxyethyl)-2-heptadecenyl-imidazoliniumchloride, and 16% glyceryl diacetate in 40 volumes of water, allpercentages being based on the weight of the fabric to be dyed. One partof the same specially knit nylon tricot fabric as employed in Example Iwas entered into the dyebath. The temperature of the bath was raised to200 F. and held at this temperature for minutes. The sample of thespecially knit tricot fabric was levelly and evenly dyed and the shadedepth variations were hardly noticeable to the eye.

EXAMPLE III A dyebath was prepared containing the following ingredients:0.5% of Pontacyl Dark Green G (CI 247 2.5% ofl,l-(Z-hydroxyethyl)2-heptadecenylirnidazolinium chloride, 5% glacialacetic acid and 40 volumes of water, all percentages being based on theWeight of the fabric to be dyed. One part of a nylon taffeta fabric wasentered into the bath and the temperature of the dyebath was slowlyraised to 200 F. and held there for 2 /2 hours. The taifeta was evenlyand levelly dyed and the fabric was well penetrated with the aciddyestuif when treated by the procedure outlined above.

EXAMPLE IV A dyebath containing the following ingredients Was prepared:0.5 of Diphenyl Brilliant Violet DB (Pr. 35), 1.0% ofl-(2-hydroxyethyl)-2-undecylimidazolinium acetate, and 2% glacial aceticacid based on the weight of the fabric to be dyed. One part of nylontaffeta fabric was entered into the dyebath. The temperature of the bathwas slowly raised to 200 F. and maintained at this temperature for twohours. The warp streaks present in the fabric were hardly noticeable.

The levelness of dying was improved by repeating the above dyeing withthe exception of substituting formic for acetic acid for pH adjustmentand adding 0.25% of the condensation product of 1 mole of stearylalcohol and 20 moles of ethylene oxide.

EXAMPLE V A dyebath was prepared containing the following ingredients:0.25% of Chromacyl Black W (Pr. 143), 1.0% of condensation product of 1mole of oleyl alcohol condensed with 15 to 20 moles of ethylene oxide,2.0% of glacial acetic acid, and 2.0% of 1,l-di-(2-hydroxyethyl)'-Z-heptadecenylimidazolinium chloride in 40 volumes of water based uponthe Weight of the fabric to be dyed. One part of the specially knitnylon tricot fabric containing seven different yarns spun underdifferent conditions was entered into the dyebath. The dyebath Wasraised F. and maintained at that temperature for 2 hours. Differences inshade between knit junctions of the specially knit fabric were hardlynoticeable.

7 EXAMPLE VI A dyebath was prepared containing the followingingredients: 0.25% Pontacyl Dark Green G (CI 247), 2.0% of formic acid,2.0% of the condensation product of stearyl alcohol condensed with 20moles of ethylene oxide, and 2.0% of1,1-di-(2-hydroxyethyl)-2-heptadecylimidazolinium hydroxide in 40volumes of water, all percentages being based on the weight of thefabric to be dyed. One part of the specially knit nylon tricot fabricknit from seven yarns of diiferent dyeing characteristics was enteredinto the dyebath. The temperature of the dyebath was slowly raised to200 F. and maintained at that temperature for 2 /2 hours. The shadevariations at the knitting junctions were hardly noticeable to the eyeafter the dyeing procedure outlined above.

EXAMPLE v11 A dyebath was prepared containing the following ingradients:1.0% Omega Chrome Orange G (CI 247), 2.0% of formic acid, 1.0 percent of1,1-di-(2-hydroxyethyl)-2-heptadecenyl-imidazolinium chloride, and 2.0%of the condensation product of 1 mole of stearyl alcohol condensed with20 moles of ethylene oxide in 40 volumes of water, all percentages beingbased on the weight of the fabric to be dyed. One part of a nylontaffeta fabric Was entered into the dyebath and the dyebath temperatureslowly raised to 200 F. This temperature was maintained for 1 hour andthe fabric then Washed and dried. The warp streaks normally occurring innylon taffeta when dyed with chrome dyestuffs were not noticeable to theeye, and the tatfeta was evenly and levelly dyed with good penetration.

It may be seen from the foregoing examples that the amount of thevarious anionic dyestuffs applied to the nylon fabrics by the methods ofthis invention are substantially those same quantities which may beapplied by conventional methods. That is, the employment of thesubstituted imidazoline compound in the dyebath does not act to increasethe susceptibility of the nylon fibers or fabrics to dyeing by thesedyes, but on the contrary provides a method for applying the same dyesmore uniformly and levelly than can be accomplished by the normalmethods.

The foregoing description makes evident the fact that this inventionprovides a practical, economical and commercial process for effectinguniform and level application of the four classes of anionic dyestuffsdemonstrating the best light and water fastness on nylon yarns andfabrics. This result has been achieved even though wide variations inthe amount of dye absorption exist when these same anionic dyes areapplied by conventional dyeing methods.

As many variations within the spirit and scope of this invention willoccur to those skilled in art, it is to be understood that the inventionis not limited to the specific embodiments thereof except as set forthin the appended claims.

I claim:

1. -A process for evenly dyeing polycarbonamide textile anticles whichcomprises dyeing the article in an aqueous acidic dyebath containing ananionic dyestufi. selected from the group consisting of direct dyes,acid dyes, acid metallized dyes, and mordant acid dyes, and from one toten times the weight of the dyestuif of a substituted imidazolinecompound selected from the group consisting of (1) a salt of animidazoline having the general formula.

C-Ra

wherein R is selected from the group consisting of alkyl,

wherein R and R are selected from the group consisting of alkyl, phenyl,hydroxyalkyl and carboxyalkyl radicals, R is an open aliphatic chainconsisting of from 10 to 18 carbon atoms and X is a halogen and (3) aquaternary imidazolinium compound having the general formula wherein Rand R are selected from the group consisting of hydroxyalkyl, alkalimetal substituted-hydroxyalkyl and alkali metal-substituted carboxyalkylradicals, and R is an open aliphatic chain consisting of from 10 to 18carbon atoms.

2. A process as defined in claim 1 wherein the anionic dyestuif is adirect dye.

3. A process as defined in claim 1 wherein the anionic dyestutf is anacid dye.

4. A process as defined in claim dyestufi is an acid metallized dye.

5. A process as defined in claim 1 wherein the anionic dyestulf is amordant acid dye.

6. A process for evenly dyeing filament polycarbonamide fabrics whichcomprises dyeing the fabrics in an aqueous acidic dyebath containing ananionic dyestuff selected from the group consisting of direct dyes, aciddyes, acid metallized dyes, and mordant acid dyes and from one to tentimes the weight of the dyestuif of a salt of an imidazoline having thegeneral formula 1 wherein the anionic wherein R is selected from thegroup consisting of alkyl, phenyl, hydroxyalkyl, and carboxyalkylradicals, and R is an open aliphatic chain consisting of from 10 to 18carbon atoms.

7. A process as described in claim 6 wherein the dyebath is maintainedat a pH of from 2.0 to 5.5 and a temperature of from 200 to 210 F. andthe dyeing is carried out for 1 to 4 hours.

8. A process as described in claim 6 wherein the salt of the imidazolineis 1-(2-hydroxyethyl)-2-undecylimidazoliniurn acetate.

9. A process for evenly dyeing filament polycarbonamide fabrics whichcomprises dyeing the fabrics in an aqueous acidic dyebath containing ananionic dyestulf selected from the group consisting of direct dyes, aciddyes, acid metallized dyes, and mordant acid dyes and from one to tentimes the weight of the dyestuif of a quaternary imidazolinium compoundhaving the general formula wherein R and R are selected from the groupconsisting of alkyl, phenyl, hydroxyalkyl, and carboxyalkyl radicals, Ris an open aliphatic chain consisting of from ten to 18 carbon atoms,and X is a halogen.

10. A process as described in claim 9 wherein the dyebath is maintainedat a pH of from 2.0 to 5.5 and a 9 temperature of from 200 to 210 F. andthe dyeing is carried out for one to four hours.

11. A process as described in claim 9 wherein the quaternaryimidazolinium compound is 1,l-di-(2-hydroxyethyl)-2-heptadecenyl-imidazolinium chloride.

12. A process as defined in claim 9 wherein the quaternary imidazoliniumcompound is 1,1-di-(2-hydroxy ethyl)-2-undecyl-imidazolinium chloride.

13. A process for evenly dyeing filament polycarbonamide fabrics whichcomprises dyeing the fabrics in an aqueous acidic dyebath containing ananionic dyestuif selected from the group consisting of direct dyes, aciddyes, acid metallized dyes, and mordant acid dyes and from one to tentimes the weight of the dyestulf of a quaternary imidazolinium compoundhaving the general formula wherein R and R are selected from the groupconsisting of hydroxyalkyl, alkali metal-substituted hydroxyalkyl andalkali metal-substituted carboxyalkyl radicals and R is an openaliphatic chain consisting of from 10 to 18 carbon atoms.

14. A process as described in claim 13 wherein the dyebath is maintainedat a pH of from 2.0 to 5.5 and a temperature of from 200 to 210 F. andthe dyeing is carried out for 1 to 4 hours.

15. A process as described in claim 13 wherein the quaternaryimidazolinium compound is 1,1-di-(2-hydroxyethyl)-2-heptadecyl-imidazolinium hydroxide.

16. A process as described in claim 13 wherein the quaternaryimidazolinium compound is the disodium salt of1-(2-hydroxyethyl)-1-carboxyethyl undecyl-imida zd linium hydroxide.

17. A process for evenly dyeing polycarbonamide textile articles whichcomprises dyeing the article in an aqueous acidic dyebath containing ananionic dyestuif selected from the group consisting of direct dyes, aciddyes, acid metallized dyes, and mordant acid dyes, from 0.1 percent to4.0 percent of a non-ionic dispersing agent selected from the groupconsisting of the condensation products of polyglycols with higher fattyacids, the condensation products of polyglycols with higher fattyalcohols, and long chain alkyl-substituted phenols, and from one to tentimes the weight of the dyestuff of a substituted imidazoline compoundselected from the group consistring of (l) a salt of an imidazolinehaving the general formula wherein R is selected from the groupconsisting of alkyl, phenyl, hydroxyalkyl, and carboxyalkyl radicals andR is an open aliphatic chain consisting of from 10 to 18 carbon atoms,(2) a quaternary imidazolinium compound having the general formulawherein R and R are selected from the group consisting of alkyl, phenyl,hydroxyalkyl and carboxyalkyl radicals, R is an open aliphatic chainconsisting of from 10 to 1 0 18 carbon atoms and X is a halogen and 3) aquaternary imidazolinium compound having the general formula Ha -N 0H-H: -N

34 Ra wherein R and R are selected from the group consisting ofhydroxyalkyl, alkali metal substituted-hydroxyalkyl and alkalimetal-substituted carboxyalkyl radicals, and R is an open aliphaticchain consisting of from 10 to 18 carbon atoms.

18. A process for evenly dyeing filament polycarbonamide fabrics whichcomprises dyeing the fabrics in an aqueous acidic dyebath containing ananionic dyestuif selected from the group consisting of direct dyes, aciddyes, acid metallized dyes, and mordant acid dyes, from 0.1 percent to4.0 percent of a non-ionic dispersing agent which is a condensationproduct of ethylene oxide with a higher fatty alcohol, and from one toten times the weight of the dyestutf of a salt of an imidazoline havingthe general formula wherein R is selected from the group consisting ofalkyl, phenyl, hydroxyalkyl, and carboxyalkyl radicals, and R is an openaliphatic chain consisting of from 10 to 18 carbon atoms.

19. A process for evenly dyeing filament polycarbonamide fabrics whichcomprises dyeing the fabrics in an aqueous acidic dyebath containing ananionic dyestuif selected from the group consisting of direct dyes, aciddyes, acid metallized dyes, and mordant acid dyes, from 0.1 percent to4.0 percent of a non-ionic dispersing agent which is a condensationproduct of ethylene oxide with a higher fatty alcohol, and'from one toten times the weight of the dyestuif of a quaternary imidazoliniumcompound having the general formula wherein R and R are selected froming of alkyl, phenyl, hydroxyalkyl, and carboxyalkyl radicals, R is anopen aliphatic chain consisting of from ten to 18 carbon atoms, and X isa halogen.

20. A process for evenly dyeing filament polycarbonamide fabrics whichcomprises dyeing the fabrics in an aqueous acidic dyebath containing ananionic dyestuif selected from the group consisting of direct dyes, aciddyes, acid metallized dyes, and mordant acid dyes, from 0.1 percent to4.0 percent of a non-ionic dispersing agent which is a condensationproduct of ethylene oxide with a higher fatty alcohol, and from one toten times the weight of the dyestuif of a quaternary imidazoliniumcompound having the general formula the group consistwherein R and R areselected from the group consisting of hydroxyalkyl, alkalimetal-substituted hydroxyalkyl and alkali metal-substituted carboxyalkylradicals and R is an open aliphatic chain consisting of from 10 to 18carbon atoms.

(References on following page) 1 1 References Cited in the file of thispatent UNITED STATES PATENTS 2,043,164 Grgnacher June 2, 1936 2,083,182Zweifel June 8, 1937 2,268,273 Wilkes Dec. 30, 1941 Douglas p. 122.

12 MacGregor Mar. 13, 1945' Smith July 19, 1955 Mooradia'n Nov. 8, 1955OTHER REFERENCES Amer. Dyestuff Rep., February 19, 1951,

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent N0a 2,952506 September 13 1960 Dimitri D., Dellis Column 5 lines 55 and 56 for"proceding" read receding column 7 line l9 for "247" read 274 Signed andsealed this 11th day of April 1961.,

(SEAL) Attest:

Attesting Oflicer Acting Commissioner of Patents

1. A PROCESS FOR EVENLY DYEING POLYCARBONAMIDE TEXTILE ARTICLES WHICHCOMPRISES DYEING THE ARTICLE IN AN AQUEOUS ACIDIC DYEBATH CONTAINING ANANIONIC DYESTUFF SELECTED FROM THE GROUP CONSISTING OF DIRECT DYES, ACIDDYES ACID METALLIZED DYES, AND MORDANT ACID DYES, AND FROM ONE TO TENTIMES THE WEIGHT OF THE DYESTUFF OF A SUBSTITUTED IMIDAZOLINE COMPOUNDSELECTED FROM THE GROUP CONSISTING OF (1) A SALT OF AN IMIDAZOLINEHAVING THE GENERAL FORMULA.